"Today we are hoping to use very large air tankers that come from Victoria to dump about 11 really large loads on the fire front," Mr Weatherill said.

"That will be so important for us to get control of this fire before those conditions worsen, so we're incredibly grateful to the Victorian and NSW Governments. Those tankers will be taking off from the RAAF base at Edinburgh so we're grateful to the Commonwealth for facilitating access to the base at short notice."

Greg Nettleton from the CFS said the top priority for firefighters was to prepare for possible catastrophic weather conditions expected to hit on Wednesday.

"We're watching very closely the weather that is coming across from the west. We are going into a warming pattern today. Tomorrow it's 38 degrees and the forecast for Wednesday is 38. The winds will swing around to the north," he said.

"At the moment I think they're predicting [winds of] about 35kph. That's enough given the dryness of the country for the fire to spread, so our number one priority is to secure the outer perimeter of that large fire so it doesn't impact on further communities."

The assistant chief officer of the South Australian Country Fire Service (CFS), Rob Sanford. said while wind speeds were not expected to increase, the high temperatures could worsen the situation.

"Those temperatures are still of a concern to us so the firefighters will be putting in a concerted effort to do everything possible to ensure that [during] the warmer weather coming in the week we won't have too many escapes from the current control line," he said.

The last thing we want to see is new fires burning inside the perimeter of the current fire and ... to lose houses in there.

Brenton Eden from the South Australian Country Fire Service

Brenton Eden from the CFS said large areas of land within the 12,500 hectare fire ground that had not been burnt were his main concern.

"We now need to concentrate on making sure in the next three to four days that there are no ember attacks into those areas, that there are no trees falling over into those areas," he said.

"Because the last thing we want to see is new fires burning inside the perimeter of the current fire and the potential to lose houses in there."

Mr Nettleton said authorities would be reopening as many arterial roads as possible on Monday, to allow people to return to their homes and assess the damage or attend to animals.

"Ideally we'd like to have everybody back to their homes, so we'll be aggressively opening up areas as we can clear those roads and making sure there's no chance of any large trees falling across the road or falling on people," he said.

"We've got arborists out examining the trees, determining which ones are safe and which ones need to be cut down."

Insurance Council declares bushfire a catastrophe

The Insurance Council of Australia has declared the bushfire a catastrophe.

The council's Campbell Fuller said that meant insurance claims by affected property owners would be given priority.

"These measures are all intended to reduce the stress on affected policy holders and better liaise with State Government, local government, emergency services and local members of Parliament, and that means that we can help provide support and resolve issues," Mr Fuller said.

Emergency relief of about $700 per family would be available to help with essential items such as food, clothing and emergency accommodation for people who cannot get back to their homes or who have lost their homes.

More than 500 firefighters battled the bushfire throughout the night as they worked to contain the blaze before an expected rise in temperatures throughout the week.

Overnight the areas under threat were at Cudlee Creek, Humbug Scrub and around the Para Wirra Recreation Park.

Victorian fires 'under control'

Meanwhile, the Country Fire Authority (CFA) in Victoria said firefighters were on top of all the state's fires, but there was still more work to be done before they were completely extinguished.

Fires at Moyston and Hastings caused the most concern over the weekend, as Victoria's firefighters battled more than 600 blazes in the past few days.

The CFA's Peter Lucas said firefighters would spend the next few days consolidating fire lines.

"Certainly, yes, [the fires are] under control and now we're going to work solidly over the next few days to get every little hot spot, every little tree stump and tree root extinguished," he said.

A reading of evidence from Senate estimates yesterday paints a different picture of the security implications of last week's debate about medevac legislation than the one generally reported, writes Laura Tingle.